94 X A4LD won't shift to second. govenor modulator

[Amac]

Hey guys,

I've been doing a ton of reading and searching on these boards the last couple of nights and would like to thank all the knowledgable people for their past experience and knowledge. (ie Brian, Glacier, etc)

So here is the story, it's a 1994 Limited with a 4.0L and A4LD tranny. It has 186,000 kilometers, (a little over 100,000 miles) and just suddenly stopped shifting into second gear a few days ago. If I rev it up to about 3500 or 4000 rpm, and then let completely off, it will shift to 3rd after a few seconds, and it will work excellent as long as I don't have to shift down to 2nd..

I was convinced that it was the speed govenor, but I popped the T-case off tonight and cleaned the govenor, gave it a light coat of Vasoline and reinstalled, but it made no difference.

Next thing on the list is to change out the modulator valve. The vacuum hose doesn't have any ATF in it, and will hold 20 inches of vacuum, but I'll give it a shot anyways..

One thing that really concerns me is that the previous owner had a Reese hitch and tranny cooler installed, which probably meant a lot of towing. The tranny fluid looks like oil and smells pretty bad.. Pretty sure I don't want to chance a fluid flush.

If the modulator valve doesn't do the trick, I'm thinking that I may drop the pan and go through the valve body. It would kind of make sense that the second gear valve just suddenly got stuck, but I'm only speculating.

Anyhoo, if anyone has any insight or ideas, I would really like to hear em..

Thanks!

 

[trollkepr]

A modulator can go bad due to the seal breaking but governors don't just go bad on themselves. It is time to pull the tranny out. You will waste your time trying to find a simple repair. It is rebuild time. Also make sure you clean the valve body really well when you are putting it back together. Replace the torque converter too. Ford trannys need to run really clean. Dirt from the TC would just end up in the valve body and just burn up your rebuild.

 

[Glacier991]

From your description I would expect possibly a broken intermediate band. You did well to check the things you did though.

And while a governor doesn't "go bad" in the classic sense, governors sticking on high mileage A4LD's and causing a cold no 1-2 shift or a cold delayed 1-2 shift are commonplace. So that was a good thing to check. If you have no 2nd at all in OD, D or manual 2, 99% certain you have an intermediate band issue. Broken, glazed or major servo leak such that it will not apply.

 

[jconnors]

I have same problem, mine started just after 12 month warranty expired on rebuild. It revs up to 3-4k then i let off gas and it catches and shifts to second fine. It has been this way for about 3 years now and has not got better or worse, only problem i have is quick constant acceleration as it wants to over rev when i pull off ramp and get on it, so i have to be careful to not blow motor.. any help would be great, i have not tried anything yet other than fluid/filter changes.

 

[Amac]

Thanks guys, I think I will go ahead and pull the tranny and go through it.. I just went through my th400, so hopefully I can get through this one with the same success.. I've seen the diary's and will pick up the ATSG for the A4LD as well.

Cheers,

 

[custom20aj]

Jconnors and Amac: Did you guys figure your trannies out??

 

[Amac]

I haven't had a chance to pull mine out yet, but hopefully this week I'll get it out and find the problem..

Cheers,

 

[old mechanic]

My 92 wasn't shifting out of first. But I manually shifted it from 1st to second and it worked fine and I used it that way for a while. Then I cleaned the Gov out and its been fine since.
I know you alwready cleaned out the gov but try manually shifting from 1st to 2nd and see if that works.

 

[custom20aj]

Amac,

I had the exact same symptoms as you, and I drove it fine that way for 6 months until we went to the Shenandoah mountains, which made me really miss second. It still drove fine, but ate my brakes and a rotor to pieces. I really didn't have a manual second either, do you?

Anyway, after rebuilding the valve body, checking the governor, and adjusting the intermediate band, I still had no second gear. This was my first experience with an automatic tranny. If I knew 3 weeks ago what I know now, my explorer would have been probably been fixed in a few hours. I ordered the part, which hasn't arrived yet, but it DID have damage. I thought maybe this could save you some time, if your only problem is ONLY second gear. You can read my thread http://www.explorerforum.com/forums/showthread.php?t=131121&highlight=specific+a4ld, BUT, knowing what I know now, this is what I would do if I were you:

1) Leave the tranny in the car (mine still is).
2) Put the car in neutral.
3) Climb under and spin the rear drive shaft by hand Both Ways to feel how free it is.
4) Tighten the intermediate band bolt until the rear drive shaft gets too hard to turn one way by hand (clockwise if looking towards the front). It will still turn free the other way. It should only take about two full turns of tightening the band bolt for you to feel the bolt getting snug, and the shaft getting hard to turn (make sure you backed the locknut off enough for it not to impede your tightening of the bolt). Glacier explains the band bolts well in his rebuild diary PART 3 2ND HALF (PAGE 3). Here is the thread for the whole diary (good reading) http://www.explorerforum.com/forums/showthread.php?t=103582&highlight=a4ld+rebuild+diary
If the shaft gets hard to turn one way as described, I would assume the band is intact (I did, but then I drove mine to confirm it, in manual 2nd only, and 2nd was there completely. I DO NOT recommend driving it, though. The shaft getting hard to spin is indication enough).
5) Back it off 1/2 turn after the shaft spins freely by hand with the same amount of effort both ways. Tighten the locknut, making sure the bolt does not turn with it. When all is said and done, you will need to replace the locknut with a new one, but not yet. Take it for a short drive (1 mile) and see if there is any change (mine didn't have any).
5) Since mine had no change, I assumed the intermediate servo was not pushing in to tighten the band, which activates second gear.
6) Pull the intermediate servo and inspect it for damage, sticking, etc... This can be easily done in car if you drop the catalytic converter (the hardest part). Again, refer to Glacier's rebuild (same page as before). Voila! My outer seal on the piston was hard as plastic, and there was a chunk missing out of it laying in the bottom of the servo hole!
7)If the servo was the problem, replace it (actually, it's worth replacing anyway. It was only about $8.00). I don't have the tool Glacier shows, but to put it back in car I have a few ideas: A. Use a REALLY big "C" clamp, which i don't have. B. Use a carpenter's wood clamp. C. Use a small bottle jack against the frame (this is probably what I'll try first, then B second).
8) Put the band bolt back to spec. (using Glacier's rebuild once again (same page as before), and drive it.
9) If 2nd gear works fine, replace the band locknut with a new one (keeping the band bolt at Glacier's spec)

If the servo would have been fine, I was thinking about having someone start it and put it in manual second (with the brake applied), the servo still removed, and checking for fluid coming into the servo area. I don't know how good that would've worked, but with everything I did, I figured all I had left were fluid passages possibly clogged.

Starting over, I would have looked at the above steps first. I hope this helps somebody.

 

[Amac]

old mechanic - I've tried manually shifting from 1 to 2, with no good results..

custom20aj - Those are some good ideas, thanks! I'd much rather keep the trans in the truck if I could, and I'm not really looking forward to the rebuild.. I'm going to give that stuff a try this weekend hopefully and will post my results..

Thanks!

 

[Amac]

I finally got some time to tinker today.. I loosened the lock nut on the intermediate band and the adjuster turned 3.5 times before it tightened up which is the exact spec my ATSG calls for.. (4.0L A4LD) When tight, the DS would only spin one way and not the other.. Good sign that the band may still be in one peice.

Next I took the exhaust down and popped the servo out. I found using a long pry bar against the floor and a shallow socket between the bar and servo cover allowed me to compress the servo enough to use my free hand to extract the lock ring. Should be no prob to revers the steps to reinstall.

I examined the seals very closely, but didn't find any marks.. I must say though, the rubber seal is hard as a rock. I'm going to get some seals and put it back together and see what happens.

One thing I did notice tho, was that the servo seal that rides against the inner ring of the servo cover doesn't seal very well.. If I cover the holes in the shaft with my fingers and work the servo in and out of the cover, it doesn't feel to me as though there is enough resistance, and that maybe there is too much blow-by..

Anyhow, I'll order the stuff on Tuesday (Monday is a holiday) and hopefully have something mid-week to play with..

Thanks again custom20aj, you may have saved me a ton of work...

Cheers,

 

[custom20aj]

Mine is fixed. I know what you mean by the seal being hard. Mine felt like hard plastic instead of rubber. The servo came in Saturday (nice and flexible), I put it together, and everything works fine. Man, am I happy! I ended up using a prybar as well. My brother pushed the servo in, and I held it in place with the prybar against the frame while he put the snap ring back on.

The servo actually comes as one piece minus the spring, cover, and cover o-ring. Here's a picture:

http://www.transhardparts.com/parts/parts/56528M.htm

This is where i got it, since we don't have any big tranny shops nearby:

https://www.transmissionpartsusa.com/ProductDetails.asp?ProductCode=230-00023952B

Wherever you get it, they needed to know the two letters on the cover (mine were BB). I hope that fixes your problem. We bought our Ex cheap because of the problem, and now it is so nice to drive it without playing with the gas pedal to go from 1st to 3rd.

Keep me posted.

 

[Amac]

Oh man, that's great news.. Hope I'm as fortunate as you.. Will keep you up to date..

Cheers,

 

[custom20aj]

Actually, I hope your more fortunate than I! I did the valve body rebuild, and checked the governor BEFORE I found the problem. Still, I only had somewhere around $130.00, and didn't have to pull the tranny, so I'm still happy. I did have a lot of time involved, but I learned a lot! I always enjoy learning, especially when it turns out for the best.

 

[Amac]

Good news! The local tranny shop stocks the servo.. ha ha, what does that tell you.. Anyways, I slapped it in when I got home and fired it up on the jackstands (with open exhaust..) and it shifts to second no problem now.. woot!

Thanks again man, you saved me a ton of work!!!

Cheers,

 

[Glacier991]

Those servos get way oveheated, in part because of the proximity to the CAT. In a pull out rebuild the $8 they cost is peanuts and man are the new ones soft compared to the "rocks" that come out. In vehicle, it's not a picnic, but as you see can be done. Good thread! Great info.

 

[custom20aj]

Glad to hear you're back in business. I've been driving mine for four days now (45 miles per day), and everything works great.

While the bolts on the catalytic are still new, I'm going to change the OD servo tomorrow as well (just for preventive maintenance).

Take care.

 

[Amac]

I had thought about that as well.. If it's a problem for the intermediate servo, why wouldn't it be a prob for the OD servo? Defenatly something to think about..

Cheers,

 

[Amac]

Bad news.. Got the exhaust all back on and took it for a drive.. I still don't have second gear!!! I'm wondering if maybe I screwed up the seal on the servo putting it back in.. I guess there could be another problem lurking somewhere as well..

Second gear works great on the jack stands, but not on the road.. Wonder what else could be wrong..

Thanks,

 

[custom20aj]

I lubed it with ATF, put the servo in the "BB" cap, and put it in as one piece.

Was there any difference in manual second?

If you're sure it was second you had on the jack stands, I would think it's the tightness of the band. I tightened mine to the spec. Glacier gave everyone (band bolt to 10 foot lbs, then backed off 2 turns). What I would do is tighten the band again until you can't turn the driveshaft the one way, back it off 1/2 turn or so, and take it for a short drive. If 2nd works, try Glacier's spec.

Like I said above, I was getting frustrated and wanted to know the band and the upper part of the tranny were definitely NOT the problem, so I tightened the band bolt to where it was fairly tight with the small wrench I was using (past the point where the driveshaft was tight one way), then I drove it in manual 2nd only, and 2nd was there completely (we have a hill on the road, so I could tell 2nd wasn't slipping). If you do try this, keep it in manual second only, go for a short drive (1 mile round trip), and don't back up (reverse felt like I had the brakes on). If yours is acting like mine, even in second if I revved it enough, first would kick in, but I could tell by the rpm's that this time it was definitely in second. This let me know the band was NOT slipping, and narrowed things down to the servo, governor, valve body, and the passages between.

If still no difference, I would assume the valve body is at fault since you already checked the governor. I did the valve body rebuild with tranny in car using Glacier's valve body rebuild diary.

Let me know if you try the band or servo again.